Pharmacology:
Acetylcysteine may decrease the viscosity of secretions by
splitting of disulphide bonds in mucoproteins. It also promotes the
detoxification of an intermediate paracetamol metabolite which is
used in the management of paracetamol overdosage.
Absorption: Rapidly absorbed from the GI tract (oral); peak
plasma concentrations after 0.5-1 hr.
Distribution: Protein-binding: 50%.
Metabolism: Extensively hepatic.
Excretion: Urine; elimination half-life: 6.25 hr (oral); 5.58
(IV).

Indications:
Acetylcysteine Solution used in Paracetamol poisoning

Dosage & administration:
Intravenous

Paracetamol poisoning
Adult: Initially, 150 mg/kg in 200 ml of infusion fluid given
over 15 minutes, followed by 50 mg/kg in 500 ml of infusion given
over the next 4 hr, then 100 mg/kg in 1 L of infusion fluid over the
next 16 hr.

Child: Child =20 kg: Initially, 150 mg/kg in
100 ml of infusion fluid given over 15 min, followed by 50 mg/kg in
250 ml of infusion given over the next 4 hr, then 100 mg/kg in 500
mL of infusion fluid over the next 16 hr. Child <20 kg: Doses as
per adult dose but adjust volume of based on child age and wt to
avoid fluid overload.

Pregnancy & Lactation:
Category B: Either animal-reproduction studies have not
demonstrated a foetal risk but there are no controlled studies in
pregnant women or animal-reproduction studies have shown an adverse
effect (other than a decrease in fertility) that was not confirmed
in controlled studies in women in the 1st trimester (and there
is no evidence of a risk in later trimesters).